Department of Radiation Oncology, IRCCS San Raffaele Scientific Institute, Milan, Italy.
Department Unit of Oncology, Medical Oncology Department, IRCCS San Raffaele Scientific Institute, Università Vita-Salute, Milano.
Tumori. 2024 Apr;110(2):116-123. doi: 10.1177/03008916231212382. Epub 2023 Nov 17.
Low skeletal muscle mass index (SMI) has recently emerged as an independent prognostic factor in oncological patients and it is linked with poor survival and higher treatment toxicity. The present study aims to determine the possible impact of low SMI on survival and acute toxicity in oropharyngeal patients.
Seventy-six patients with locally advanced oropharyngeal squamous cell carcinoma (stage III-IVC) were treated in our institution with Helical TomoTherapy® (HT - Accuray, Maddison, WI, USA) between 2005 and 2021. All patients received concomitant platinum-based chemotherapy (CT) (at least 200 mg/m2). The SMI was determined using the calculation of cross-sectional area at C3. Twenty patients (26%) presented pre-treatment low SMI, according to Chargi definitions.
All patients concluded the treatment. Thirteen patients with low SMI (65%) and 22 patients with normal SMI (39%) presented acute toxicity greater than or equal to grade 3, but this difference was not statistically significant (p-value = 0.25). Overall survival was analyzed in 65 patients, excluding those who finished CT-RT less than six months before the analysis. Overall survival was significantly lower in low SMI versus normal SMI patients (p-value = 0.035). Same difference was observed in N0-N2a patients, suggesting an important role of SMI also in lower nodal burden and putatively better prognosis.
Although the results are limited to a small population, our case series has the advantage to be very homogeneous in patients and treatment characteristics. In our setting, SMI demonstrated a crucial impact on overall survival. Further investigation with larger samples is necessary to confirm our results to improve patient outcomes.
低骨骼肌指数（SMI）最近已成为肿瘤患者的独立预后因素，与生存不良和更高的治疗毒性相关。本研究旨在确定低 SMI 对口咽癌患者生存和急性毒性的可能影响。
2005 年至 2021 年间，我们机构对 76 例局部晚期口咽鳞状细胞癌（III-IVC 期）患者采用螺旋断层放疗（HT-Accuray，Maddison，WI，美国）进行治疗。所有患者均接受顺铂为基础的同期放化疗（CT）（至少 200mg/m2）。SMI 采用 C3 横截面积计算确定。根据 Chargi 定义，20 例（26%）患者存在治疗前低 SMI。
所有患者均完成治疗。13 例低 SMI 患者（65%）和 22 例正常 SMI 患者（39%）出现≥3 级急性毒性，但差异无统计学意义（p 值=0.25）。排除分析前 CT-RT 结束时间不足 6 个月的 65 例患者进行总生存分析。低 SMI 患者的总生存明显低于正常 SMI 患者（p 值=0.035）。在 N0-N2a 患者中也观察到相同的差异，提示 SMI 对淋巴结受累程度较低和潜在的更好预后也有重要作用。
尽管结果仅限于小样本人群，但本病例系列在患者和治疗特征方面具有很大的优势。在我们的环境中，SMI 对总生存有重要影响。需要进一步进行更大样本的研究以证实我们的结果，从而改善患者的预后。
